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P Mula,
C Pilo,
C Solinas,
A P Pipia,
A Varcasia,
I Francisco,
M S Arias,
A Paz Silva,
R Sánchez-Andrade,
P Morrondo,
P Díez-Baños, A Scala
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ABSTRACT: From January to December 2008, 265 horses slaughtered in Sardinia (Italy) were examined for the presence of Rhinoestrus spp. (Diptera: Oestridae) through the examination of the nasal cavities and pharynges. Larvae were detected in 49% of the horses, with a mean intensity of infestation of 16.09 and abundance of 7.95. A total of 2108 larvae were collected, 66% of which were classified in first instar (L1), 22% in second instar (L2) and 12% in third instar (L3). The most frequent localization of larvae was the ethmoid, while the less one the larynx. According to the dynamics of Rhinoestrus larval stages, three periods in the chronobiology can be considered, the diapause (September-February) characterized by an absolute prevalence of first larval stage; the active phase of the endogenous phase (February-September) with an increase in the percentages of L2 and L3, and the exit phase (May-September), pointed by a further increase of L1. Morphological examination of L3 larvae revealed the presence of the Rhinoestrus purpureus features in 8% of the examined larvae, of 8% of the Rhinoestrus usbekistanicus features, while in 84% of the larvae were evidenced intermediate features. Contrastingly biomolecular analysis of the COI gene of the larvae evidenced uniformity at genetic level, confirming the presence of a unique species in the Mediterranean area. The results of the present paper, reveal the wide diffusion of rhinoestrosis among Sardinian horses, and suggest the need for applying appropriate control measures. Chemotherapy should be very useful if administered during the diapause period, for reducing the presence of L1 stages and interrupting thus the life cycle of this myiasis.
Veterinary Parasitology 10/2012; · 2.58 Impact Factor
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R Sánchez-Andrade,
F J Cortiñas,
I Francisco,
J A Sánchez,
P Mula,
C Cazapal,
L Vázquez,
J L Suárez,
R Francisco,
M S Arias,
P Díez-Baños, A Scala,
A Paz-Silva
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ABSTRACT: We have developed a novel enzyme-linked immunosorbent assay (ELISA) based on excretory/secretory antigens of second instar Gasterophilus for the diagnosis of gasterophilosis in grazing horses. Between January 2007 and January 2009, two experiments were carried out on free-ranging horses in northwest Spain. During the first year, monthly blood samples were collected from a herd of 25 horses. In the second year, a monthly serological survey was conducted for a total of 398 different horses. All the sera were analyzed by ELISA using excretory/secretory antigens from Gasterophilus intestinalis (GphiL2ES) and Gasterophilus nasalis second-stage larvae (GphnL2ES). Climatic data were collected between January 2007 and January 2009 from local meteorological automated stations to establish the weather pattern in the study area. Observations of Gasterophilus eggs on the horses' hair and third instars passed in the faeces were also done. The kinetics of IgG response decreased against GphiL2ES from January to July, increased slowly from August and rose up to January. After a slight decrease in January, the absorbances against GphnL2ES reduced from April to August, when the lowest values were observed. The IgG values rose until the end of the study in January. Third instars were observed in the faeces in March to May, and Gasterophilus eggs were seen on the horses' hair from June to September. The highest IgG seroprevalences were achieved in winter (January-February; 100%) against both antigens. The lowest percentages of seropositivity were observed in June (3%) to the GphiL2ES, and in July (9%) to the GphnL2ES. The use of antigens from G. intestinalis second-stage larvae was shown to be suitable for diagnosing infestation by G. intestinalis or G. nasalis. We concluded that under oceanic climate conditions, the egg-laying period occurs from late spring, and eggs and first instars are found in the mouth in early summer. During summer the second instars move into the stomach and intestine, where the third-stage larvae remain until the end of winter, when pupation takes place. The adult horse bot fly emerges in the spring. Two treatments for the control of gasterophilosis are suggested: a curative in the summer to eliminate the first instars and a preventive in the autumn to suppress the second instars.
Veterinary Parasitology 08/2010; 171(3-4):314-20. · 2.58 Impact Factor
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J A Romero,
M S Arias,
J L Suárez,
A Paz-Silva,
I Francisco,
F Alonso,
F J Cortiñas,
V Dacal,
A Romasanta,
P Morrondo,
P Díez-Baños, A Scala,
R Sánchez-Andrade
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ABSTRACT: The analysis of immunoglobulin (Ig) M and IgG serum isotypes as indicators of the presence of Oestrus ovis developmental stages was carried out. A serological survey to discover the seasonal variations in the prevalence of oestrosis in sheep from an oceanic climate area was developed. Six hundred and sixty-nine blood samples were analyzed for the presence of IgM and IgG using an enzyme-linked immunosorbent assay and O. ovis second-stage larvae excretory/secretory antigens. In addition, the effect of an ivermectin-based treatment on the humoral immune response was measured. The percentage of positive animals was 54% for IgM and 55% for IgG. The highest percentages of sheep positive to IgM were recorded in the winter and to IgG in the summer. No animals positive to IgM were detected in the ivermectin-treated sheep. These results seem to underline that oestrosis is a parasitic disease to keep watch for in regions with an oceanic climate. A noninvasive evaluation of the success of chemotherapy seems possible by analyzing the serum IgM response.
Journal of Medical Entomology 05/2010; 47(3):477-81. · 1.76 Impact Factor
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ABSTRACT: Antibody responses (IgG, IgM and IgA) against Oestrus ovis were analyzed in sheep and in first year grazing lambs from Sardinia (Italy) by an indirect-enzyme-linked immunoassay test and L2 O. ovis excretory/secretory antigens. Serum samples from 208 sheep were obtained prior to be slaughtered, and then heads were removed and cut open along their longitudinal axis to collect the parasites from the nasal cavities, turbinates and sinus. Besides this, blood samples were monthly collected from the lambs of G-1 (maintained under field conditions) and the lambs of G-2 (kept housed since birth to avoid Oestrus infestations) throughout a year. In the sheep, a positive significant correlation was observed between the number of first instar O. ovis larvae and the values of IgM, and between the second instar larvae and the IgG optical densities. In the lambs, all classes of antibodies increased significantly from July in G-1. The highest values of IgG were reached in September (IgG) and decreased in November-December. The IgM response peaked in November, and very low values of IgA were observed during the study. Matching these data with chronobiology of O. ovis in this region, we conclude that the first infection occurs on May, stimulating the production of humoral antibodies. The reduction of the IgG antibody levels starting from October means the beginning of the diapause while the IgM response seems to be associated to the presence of L1 in the nasal cavities. The data obtained led us to forecast an early treatment of the ovine on June-July, which should keep away from the maturation of O. ovis L1 larvae, avoiding the development of clinical lesions and interrupting the life cycle of this parasite.
Veterinary Parasitology 12/2005; 134(1-2):153-8. · 2.58 Impact Factor
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R Sánchez-Andrade,
J L Romero,
J L Suárez,
J Pedreira,
P Díaz,
M Arias,
A Paz-Silva,
R Panadero,
P Díez-Baños,
P Morrondo, A Scala
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ABSTRACT: Control of zoonosis implies reduction of infected animal hosts, and the first measure consists of a suitable and accurate detection test. An experimental study for determining the most appropriate antigen (metabolic or somatic) to be used in the detection of the oestrosis (Oestrus ovis) zoonotic myasis by means of immunoenzymatic probes was carried out. A flock of 23 uninfected goats was maintained under field conditions to allow their infection in Sassari (Sardinia, Italy). Caprine were bled monthly and serum samples processed by means of an iELISA. After comparing these results to the chronobiology of O. ovis, we proved that the IgG humoral response against the metabolic antigens increased only during the period of real risk of infestation (when adults fly, from May to September), whereas the absorbances against the somatic products were positive from the beginning of the study (in January, prior to infection). We concluded that the excretory/secretory products are most useful and suitable for the immunodiagnosis of oestrosis in goats, because a direct relation between the development of O. ovis and the IgG humoral response is possible, allowing a more accurate diagnostic.
Immunological investigations 02/2005; 34(1):91-9. · 1.16 Impact Factor
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ABSTRACT: An indirect enzyme-linked immunosorbent assay (ELISA) with Dicrocoelium dendriticum excretory/secretory antigens was used to evaluate the presence of serum antibodies against the trematode in 738 sheep randomly chosen in Sardinia (Italy). Coprological sedimentation was used to discover egg-output. Seropositivity was detected in 86.2% tested sheep, whereas faecal prevalence was 6.7%; all that were faecal-positive also were ELISA-positive.
Preventive Veterinary Medicine 03/2003; 57(1-2):1-5. · 2.05 Impact Factor
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ABSTRACT: Oestrus ovis (Linné 1761) larvae are obligatory parasites of the nasal and sinus cavities of sheep and goats. Infestation is prevalent in hot and dry regions, such as Mediterranean countries. The current work was developed to establish the chronobiology of O. ovis in Sardinia, to determine the most suitable time for chemoprophylaxis. A survey was carried out during 1998, and sheep heads were collected monthly from local flocks. A total of 443 heads was examined, and the prevalence of oestrosis was 73.8%. We collected 2,691 larvae (mean = 6.07 +/- 9.52), and the intensity was greatest in November. The humoral immune response against the nasal bot fly was analyzed by means of an indirect-ELISA using second-instar O. ovis excretory and secretory antigens. A seasonal variation in the antibody levels was observed, increasing from April and peaked in June and in September. A significant correlation was observed between first instar intensity and the mean relative humidity (r2 = 0.120; P < 0.05), and between second-instar intensity and the mean temperature (r2 = 0.241; P < 0.05). Three periods in the chronobiology of O. ovis were defined: diapause (October-February), the active phase ofthe endogenous cycle (March-September) and the exit phase (May-September). Our results showed that treatment in October-November was suitable, because first instars were in diapause, preventing the development of first into second instars, and second into third instars.
Journal of Medical Entomology 07/2002; 39(4):652-7. · 1.76 Impact Factor
